| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for manufacturing a glass substrate, capable of suppressing temperature drop in the vicinity of an electrode to reduce platinum foreign matters of the glass substrate.SOLUTION: In a method for manufacturing a glass substrate including a refinement step of refining a molten glass including tin oxide while heating the molten glass, a refiner comprises: a platinum tube 400 for refining the molten glass; at least a pair of flange shaped electrodes 50 provided in the platinum tube 400; and cooling tubes 502 for cooling the electrodes 50. In the refinement step, in order to make a temperature difference between a temperature of the central portion of the platinum tube 400 in a longitudinal direction and a temperature in the vicinity of the electrode 50 in the vapor phase space of the platinum tube 400 be equal to or less than a predetermined temperature at which a volatilized platinum included in the vapor phase space of the platinum tube is coagulated in the vicinity of the electrode, the diameter or thickness of the electrode is determined on the basis of a relational expression between the diameter or thickness of the electrode previously determined and the temperature difference. |
